Assessment and Diagnostic Evaluation for disorders and diseases of Kidney and Urinary tract system
The urinary and renal system include kidney, urinary bladder, ureters and urethra.Kidney forms the urine.
Renal and Urinary tract system:
There are 2 bean shaped kidneys in us.They are brownish-red in color. The right kidney is a bit lower than the left kidney. It is because of liver location. Kidneys are protected by back and abdomen muscles and the ribs.
Kidney blood supply
The kidney receives 20% to 25% of the total output from the heart.All the blood of the body circulates approximately 12 times per hour through the kidney.
These are responsible for initial formation of urine.The nephrons allow renal function even if opposite kidney becomes nonfunctional.Renal replacement therapy is considered if total nephron's functioning is less than 20% of normal.
Urinary bladder, ureter and urethra
The urine formed in nephron's passes through renal pelvis and then to ureters.Ureters are fibromuscular tubes that connect kidney to bladder. Left ureter is a little shorter than right ureter.Urine movement from renal pelvis through ureter into bladder is by peristaltic contraction of muscles in ureter wall.
Renal and urinary tract system function
Human body is composed of 60% water.Regulation of water balance is regulated by kidneys. This results in urine formation. Formation of urine is in nephron's by 3 step process:glomerular filtration,tubular reabsorption, tubular secretion. The substances filtered,reabsorbed and excreted in urine include bicarbonate, sodium,potassium, chloride, glucose, uric acid,creatinine, urea.Selectively some of these substances are reabsorbed in blood within tubule.Others are sent from blood into filtrate.
Filtration by glomerulus
1200 ml/min blood flows through the kidney. Filtration takes place when blood flows into glomerulus.About 20% of blood that passes through glomerulus is filtered into nephron,that is 180 L/day of filtrate. The filtrate has electrolytes, water and other molecules of small size because these small molecules and water pass whereas molecules which are large stay in bloodstream.
Reabsorption by tubules and secretion by tubule
The second, third step of formation of urine occur in renal tubules.A substance moves from filtrate back to peritubular capillaries in tubular reabsorption and in tubular secretion a it moves from perotubular capillaries into tubular filtrate. 99% of filtrate is reabsorbed into blood stream of 180 L produced by kidney each day.This results in 1L to 2L urone formation each day. Reabsorption is along entire tubule.
This hormone is known by the name of vasopressin.It is secreted when changes in osmolality of blood take place.Pituitary gland secretes it.When there is a decrease in water intake,blood osmolality increases.This stimulates the release of ADH.In response ADH acts on kidney, this increases reabsorption of water resulting in osmolality of blood returning to normal.
Risk factor for urologic or renal disorder
Urologic or renal disorder
Chronic disease of kidney,neurogenic bladder
multiple myeloma,sickle cell anaemia
chronic disease of kidney
renal insufficiency,chronic renal failure
formation of kidney stones
Pain,gastrointestinal symptoms, changes in voiding are suggestive of disease of urinary tract.Dysfunction of kidney produces symptoms that are throughout the body.
Geritourinary pain is due to distention of urinary tract due to obstructed flow of urine or inflammation and swelling of the tissues.
These symptoms are associated with the urologic conditions. The proximity of right kidney to colon,pancreas, duodenum, liver may result in gastrointestinal disturbances. The proximity of left kidney to stomach, spleen,pancreas may cause intestinal symptoms.
Micturition is a painless function. It happens 8 times in a 24 hour period.
The problems which are commonly associated with voiding are incontinence, polyurea,frequency, dysurea,urgency, hematurea.
History of health is required to determine the lab and diagnostic tests.Following are some tests that might be used.
Culture of Urine and Urinalysis
Urinalysis provides clinical information about the function of kidney and helps in the diagnosis of diseases like diabetes.
Urine culture, sensitivity helps in identification of the antimicrobial therapy.
Renal function tests are renal concentration test,blood urea nitrogen, serum creatinine,creatinine clearance.
Renal Function Tests
renal concentration test
300-900 mOsm/kg/24 h,50-1200 mOsm/kg random sample
urea nitrogen in blood(BUN)
BUN to creatinine ratio
Biopsy of the kidney helps in the diagnosis and evaluation of the extent of kidney disease.